The carbon stored under Antarctic ice is on par with the amount held in the northern hemisphere’s frozen permafrost soils and the lower end of estimates for methane trapped under the Arctic Ocean, according to Jemma Wadham, professor of Glaciology at the U.K.’s University of Bristol and lead author of a study in the journal Nature yesterday.

(Photographer: Torsten Blackwood/AFP/Getty Images)

An enormous and previously unknown reservoir of potent methane—a greenhouse gas 25 times more potent than carbon dioxide—could be locked beneath the Antarctic ice sheet, a new study in the journal Nature warns.

The scientists behind the study calculate that as much as 4 billion tons of methane gas could exist beneath the ice, and that if the alarming rate of polar melting continues and the vast reserve escapes into the atmosphere, the feedback loop of climate change already underway would accelerate dramatically.

If the scientists are correct, these southern deposits would roughly match recent estimates of the amount of methane lurking beneath the northern Arctic ice sheets.

3. Yep, that's the one that freaks me out.

It's going to be like living at 12,000 feet all the time if that methane gets dumped in the atmosphere in a short period, and the West Antarctic ice sheet is not thought to be all that stable. Could raise the sea level a bit too ...